What is systems engineering about? Engineering is “the application of science and mathematics by which the properties of matter and the sources of energy in nature are made useful to people” (Merriam-Webster) . Some dictionaries include “principles” in addition to science and mathematics.
Traditional engineering focuses on specific physical areas. Civil engineering is about structures: roads, bridges, buildings. Mechanical engineering is about machines: turbines, engines, etc. Systems engineering sits at a higher conceptual level. It focuses on systems, which is the combination of all the different products of the different engineering specialties.
Engineering is about trade-offs. Engineers use their knowledge to maximise the value if the product they are working on, making sure it meets the purpose of the product, at a price, quality, reliability, etc that is required.
Systems engineering is entirely the same but focuses on maximising the value of the system (the interacting combination of the different artefacts).
A civil engineer trades bridge strength and capacity with cost. They can design a bridge that can carry 100 60 ton main battle tanks at the same time, but at a cost that is prohibitive and does not return value to the sponsor.
A systems engineer trades the characteristics of the bridge with the characteristics of the other entities that interact with the bridge. For example how the bridge serves the needs of a nearby shipping port or the generational growth of the population being served.
In other words, the SE describes the requirements - the mission, characteristics desired, and the constraints of a bridge, the civil engineer designs the most appropriate bridge to meet the requirements.
